In the related-art air conditioning apparatus using a refrigeration cycle (heat pump cycle), a heat source device-side unit (e.g., heat source device or outdoor unit) including a compressor and a heat source device-side heat exchanger and a load-side unit (e.g., indoor unit) including a flow control device (e.g., an expansion valve) and an indoor unit-side heat exchanger are connected to each other by refrigerant pipes to constitute a refrigerant circuit configured to circulate refrigerant. A phenomenon in which the refrigerant is evaporated or condensed in the indoor unit-side heat exchanger by receiving or transferring heat from or to air in an air-conditioned space that is a heat exchange target is used to condition the air by changing a pressure, a temperature, and other related factors of the refrigerant in the refrigerant circuit.
In this case, for example, an existing air conditioning apparatus is capable of performing a simultaneous cooling and heating operation (cooling and heating mixed operation) in which a plurality of indoor units can each automatically determine whether cooling or heating is suitable depending on a temperature set by a remote controller provided to the indoor unit and an air temperature around the indoor unit to perform cooling and heating with each indoor unit (see, for example, Patent Literature 1).
In addition, an existing air-conditioning apparatus is configured to obtain a target value of an outlet temperature of a heat medium to be supplied to the heat source device-side heat exchanger based on a predefined relationship from an inlet temperature of the heat medium and a frequency of the compressor and control a frequency of a heat-medium conveying device (for example, a water pump) to approximate the target value (see, for example, Patent Literature 2).